Agent Orange was the codename for a powerful vegetation killer used by the U.S. military during the Vietnam War. It was named after the orange-striped barrels it was shipped in, and was later linked to causing health problems for people who had been exposed to it.

The character also has a resemblance to Robert Patrick, who played the T-1000 in Terminator 2: Judgement Day, and later an FBI agent in the X-Files.

Agent Orange used to date Sinthea. According to her bio, he was killed after/during the first game, making him one of only two mentioned fatalities of the whole franchise!. The other being the second grimm brother in Carmageddon Reincarnation

Leadpumper was most likely an actual lead pumper, considering it would have been built to run on leaded petrol.

To 'pump someone full of lead' is to kill them by shooting them repeatedly, 'pumping' lead bullets into their bodies.

In the German version, Agent Orange is a mad ex-BND agent. The BND (short for Bundesnachrichtendienst) is the German intelligence service.